Question: $ { \left[\begin{array}{rr}{-2} & {4} \\ {1} & {3} \\ {-1} & {3}\end{array}\right]+\left[\begin{array}{rr}{-1} & {-2} \\ {2} & {4} \\ {2} & {3}\end{array}\right] = {?} } $
Explanation: To find the sum of two matrices, add the corresponding items between each matrix. ${\left[\begin{array}{rr}{-2}+{-1} & {4}+{-2} \\ {1}+{2} & {3}+{4} \\ {-1}+{2} & {3}+{3}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{rr}{-3} & {2} \\ {3} & {7} \\ {1} & {6}\end{array}\right]}$